Extruded Deposition of Polymers Having Continuous Carbon Nanotube Reinforcements

Abstract

A composite part is fabricated by rastering a deposition head over a substrate, and additively forming part features by extruding a polymer having an entrained continuous nanotube reinforcement from the deposition head onto a substrate.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of prior U.S. patent application Ser. No. 14 / 489,972 filed Sep. 18, 2014, the entire disclosure of which is incorporated by reference herein.BACKGROUND INFORMATION[0002]1. Field[0003]The present disclosure generally relates to additive manufacturing techniques, and deals more particularly with a method and apparatus for deposition of polymers having continuous nanotube reinforcements.[0004]2. Background[0005]Additive manufacturing is a process in which physical parts are produced directly from a 3-D (three dimensional) CAD (computer aided design) file. In one type of additive manufacturing known as fused deposition modeling (FDM®) and sometimes referred to as 3-D printing, a part is produced by extruding small beads of thermoplastic polymer material to form layers of the material that solidifies after being extruded from a nozzle. The extrusion nozzle may be moved along a toolpath or “rastered” b...

AI Technical Summary

Benefits of technology

The patent describes a way to make strong and detailed parts using a special method called additive manufacturing. This method involves adding a type of material called continuous carbon nanotubes (CNTs) to a melting polymer as it is being deposited in layers to form the part. This results in parts that are stronger and have improved mechanical properties. The CNTs act as reinforcement for the polymer, making it more durable and increasing its ability to withstand mechanical stress. The disclosed embodiments allow for the fabrication of parts that have fine details and high print resolution.

Problems solved by technology

In some applications, however the use of discontinuous fiber reinforcements such as chopped fibers may not provide the required mechanical strength.

While the use of continuous fiber reinforcements is possible in extruded type additive manufacturing processes, limitations exist in the types of parts that can be produced, particularly those having finely detailed features that require relatively small print resolution.

These limitations stem from the fact that known continuous fiber reinforcements are limited in the radial length in which the continuous fiber reinforcement can be bent, due to their stiffness

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